Chemistry, Quarter 1, Unit 1.1
Kinetic Molecular Theory/Physical
and Chemical Changes
Overview
Number of instructional days:
10
(1 day = 53 minutes)
Content to be learned
Processes to be used
•
Use appropriate data related to chemical and
physical properties to distinguish one substance
from another.
•
Compare and contrast physical and chemical
properties of matter.
•
Use appropriate data related to chemical and
physical properties to identify an unknown
substance.
•
Make observations to classify changes of
matter as physical or chemical.
•
Model the gas, liquid, and solid states in terms
of particles and their interactions.
•
Define and give examples of plasma.
•
How does a chemist use different physical and
chemical properties to identify an unknown
substance?
•
Explain the states of matter in terms of the
particulate nature of matter.
Essential questions
•
What are the organizations and relative
energies of particles in the four states of
matter?
•
How does a scientist classify changes of
matter?
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
C-1
Chemistry, Quarter 1, Unit 1.1
2010-2011
Kinetic Molecular Theory/Physical
and Chemical Changes (10 days)
Final, July 2011
Written Curriculum
Grade Span Expectations
PS1 - All living and nonliving things are composed of matter having characteristic properties that
distinguish one substance from another (independent of size or amount of substance).
PS1 (9-11) INQ –1
Use physical and chemical properties as determined through an investigation to identify a substance.
PS1 (9-11)–1 Students demonstrate an understanding of characteristic properties of matter
by …
1a utilizing appropriate data (related to chemical and physical properties), to distinguish one
substance from another or identify an unknown substance.
PS1 (Ext)–1 Students demonstrate an understanding of characteristic properties of matter
by …
1aa explaining the states of a substance in terms of the particulate nature of matter and the forces
of interaction between particles.
Clarifying the Standards
Prior Learning
In grades K–2, students recorded and explained their observations as they grouped and sorted objects by
physical properties. In grades 3–4, students learned how to sort objects using temperature and flexibility
as they observed and described a change of state (e.g., freezing and thawing). In the fifth and sixth grades,
students compared masses of objects of equal volume that were made of different substances. In eighth
grade, they learned to measure mass and volume of both regular and irregular objects and to use those
values along with the relationship D = m/v to calculate density.
Current Learning
Since students have not had previous experiences with this content, instruction should begin at the
developmental level. This content will not be addressed in future courses, therefore it must be taken to the
level of drill and practice (mastery level).
Students examine physical and chemical properties of known substances and use those properties to help
them identify an unknown substance. Within an investigation, students utilize appropriate data to
distinguish changes of matter as physical or chemical; they also distinguish gas, liquid, and solid states in
terms of particles and their interactions. Models are created and used to illustrate the three states of matter
(solid, liquid, gas). Students also define and give examples of plasma.
Future Learning
Students will describe how pressure and temperature relate to the volume of a gas. Advanced students
will quantitatively determine how the volume, pressure, temperature, and amount of a gas affect each
other (PV = nRT).
C-2
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
Kinetic Molecular Theory/Physical
and Chemical Changes (10 days)
Final, July 2011
Chemistry, Quarter 1, Unit 1.1
2010-2011
Additional Research Findings
According to the Atlas of Science Literacy and Making Sense of Secondary Science, the concept of energy
transformation among the different states of matter should have been taught prior to this unit (Atlas, p. 57;
Making Sense, pp. 79–83).
Frequently, the concept that gases have mass and take up space is difficult for students to grasp; therefore
it may be necessary to further explain the particle nature of gases. One suggested activity to help with this
misconception is to mass an empty balloon, then have a student inflate the balloon, and mass it again. The
small but measurable mass difference should clarify student understanding.
Research indicates that younger children tend to regard any rigid material as a solid, any powder as a
liquid, and any nonrigid material—for example, a sponge or cloth—as intermediate between a solid and a
liquid. Pupils explained that powders are liquids because they can be poured and that nonrigid materials
are intermediate because they are soft, they crumble, or they can be torn. Thus, children decided the state
of a material according to its appearance and behavior, with the result that they associated solidity with
hardness, strength, and nonmalleability.
At age 11, pupils tend to regard powders as intermediate states rather than solids. Teachers might
emphasize that powders are composed of small solids. However, researchers also caution that when
students are subsequently learning the particulate theory of solids, they may wrongly infer that the
theoretical particles are “powder grains.” Therefore, it is suggested that students first be comfortable with
classifying materials according to the scientific view of the states of matter prior to learning particulate
theory.
Children appear to identify a liquid as any material that is runny or can be poured. Consequently, their
view of liquids includes powders. Further, in a child’s view, if the exemplary liquid is water, then all
liquids may be regarded as water. Children may regard the liquid form of a material as having less weight
than the same mass of its solid form.
Researchers have studied students’ conceptions of gases, and found that students do not initially appear to
be aware that air and other gases possess material character. It is common for students to think that air and
gas have contrasting affective connotations—for example: Air is good because it’s used for breathing and
life, whereas gas is bad because it may be poisonous, dangerous, or inflammable.
When interviewed about what happens to a block of ice on a teaspoon, only 8 out of 43 students described
the melting of ice in particle terms. Generally, pupils held the view that heat makes the particles move
further apart. They appeared to use the underlined model that the volume of substances increases as its
temperature rises, when unfortunately this model does not apply to melting ice.
Researchers found that pupils express the freezing process in terms of particles becoming more packed
together. This idea may lead students to reason that water in its solid form (ice) doesn’t take up as much
room as in its liquid or gaseous forms. Even though some pupils have been taught about latent heat and
hydrogen bonding, none of them mentioned these concepts when explaining freezing.
When interviewed about what happens to water evaporating from a plate, only 8 out of 43 pupils
mentioned particles are molecules. At least one was aware that the particles were “getting energy from
somewhere and flying off.”
Pupils often regard atoms as small bits of solid or liquid that are static, nonuniform, and without cohesive
force. Children appear to think that such bits vary in size and shape, having no space between them.
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
C-3
Chemistry, Quarter 1, Unit 1.1
2010-2011
Kinetic Molecular Theory/Physical
and Chemical Changes (10 days)
Final, July 2011
Researchers concluded that secondary school pupils understood most attributes of the particle model one
at a time, but were unable to unify all particle behavior within a single concept.
Pupils aged 13 to 14 regarded the liquid state as halfway between solid and gas. As a result, pupils held
ideas that greatly overestimated the spacing and speed of the particles of a liquid. The researchers suggest
that, based on the pupils’ misconceptions, a liquid would allow molecules to just move apart from each
other. The liquid would also be compressible. Therefore, the pupils’ model would not allow for
explanation of evaporation.
Sixty percent of young adolescents indicated that gas is composed of particles; 46 percent said that there
is empty space between particles; 50 percent said that intrinsic motion accounts for the distribution of
particles in space.
Notes About Resources and Materials
C-4
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
Chemistry, Quarter 1, Unit 1.2
Atoms and Molecules
Overview
Number of instructional days:
10
(1 day = 53 minutes)
Content to be learned
Processes to be used
•
Explain how advances in technology have
changed the understanding of atomic structure.
•
Conduct research about the structure of atoms.
•
Use data to explain how the understanding of
atomic structure has changed.
•
Compare and contrast the three subatomic
particles of atoms in terms of location, mass,
and charge.
•
Compare the three subatomic particles of atoms
(protons, electrons, neutrons).
•
Use data such as diagrams, charts, and
narratives.
•
Compare the location within an atom, the
relative mass, and the charge of the subatomic
particles that make up an atom.
Essential questions
•
How have advances in technology changed our
understanding of atomic structure?
•
How is the current model of the atom different
from previous models?
•
How are the three major subatomic particles
similar and different?
•
How would you describe the current model of
the atom in terms of the subatomic particles
and their location within the atom?
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
C-5
Chemistry, Quarter 1, Unit 1.2
2010-2011
Atoms and Molecules (10 days)
Final, July 2011
Written Curriculum
Grade Span Expectations
PS1 - All living and nonliving things are composed of matter having characteristic properties that
distinguish one substance from another (independent of size or amount of substance).
PS1 (9-11) MAS+ NOS –2
Scientific thought about atoms has changed over time. Using information (narratives or models of atoms)
provided, cite evidence that has changed our understanding of the atom and the development of atomic theory.
PS1 (9-11)–2 Students demonstrate an understanding of characteristic properties of matter
by …
2a using given data (diagrams, charts, narratives, etc.) and advances in technology to explain how
the understanding of atomic structure has changed over time.
PS1 (9-11) MAS+ FAF – 4
Model and explain the structure of an atom or explain how an atom’s electron configuration, particularly the
outermost electron(s), determines how that atom can interact with other atoms.
PS1 (9-11)– 4 Students demonstrate an understanding of the structure of matter by …
4a comparing the three subatomic particles of atoms (protons, electrons, neutrons) and their
location within an atom, their relative mass, and their charge.
Clarifying the Standards
Prior Learning
The concept of atoms and molecules was introduced in grades 5–6. In grade 6, students learned that,
regardless of sample size, a substance can be identified by its properties. Students also learned to
differentiate the characteristics of solids, liquids, and gases.
In grades 7–8, students created diagrams and/or models to represent the states of matter at the molecular
level, and they identified an unknown substance given its characteristic properties.
Current Learning
Students cite evidence for the development of the historical models of the atom, starting with Dalton’s
atomic theory and continuing through the experiments of J.J. Thompson and Ernest Rutherford. The
various modifications of the atomic model through the late 19th and 20th centuries are diagrammed.
Students conduct investigations that simulate working with unknown structures.
Students compare the location of the three major subatomic particles of atoms (protons, electrons, and
neutrons) and their location within an atom, their relative mass, and their charges.
Students have previously learned basic atomic structure (middle school–grade 9). This unit adds historical
detail to the models.
C-6
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
Atoms and Molecules (10 days)
Final, July 2011
Chemistry, Quarter 1, Unit 1.2
2010-2011
Future Learning
In advanced chemistry classes, students will learn to write electron configurations to include s, p, d, and f
orbitals. They will also relate to atomic interactions.
As part of the extension standards in biology, students will explain the energy transfer between cells in
photosynthesis and cellular respiration, tracking ATP production and consumption (electron transfer
chain).
Additional Research Findings
According to Making Sense of Secondary Science, students may mistakenly think that atoms are solid
spheres. They also greatly exaggerate the distance among components of atoms. Physical and computer
models should be used to help students accurately visualize atom structure. Students may also confuse the
relative sizes of subatomic particles, especially the size of electrons, which are difficult to conceptualize
(pp. 73–77).
Additionally, the Atlas of Science Literacy states that, to understand the content in this unit, students need
to comprehend that the 100+ elements identified to date are the foundation for all matter and that these
atoms are too small to be seen, even with a microscope. Finally, students should recognize that, while any
given element’s atoms are alike, they are different from atoms of other elements (p. 55).
Notes About Resources and Materials
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
C-7
Chemistry, Quarter 1, Unit 1.2
2010-2011
C-8
Atoms and Molecules (10 days)
Final, July 2011
Cranston Public Schools, in collaboration with
the Charles A. Dana Center at the University of Texas at Austin
Chemistry, Quarter 1, Unit 1.3
Nuclear Changes
Overview
Number of instructional days:
7
(1 day = 53 minutes)
Content to be learned
Processes to be used
•
Explain how the nuclear make-up of atoms
governs alpha and beta emissions.
•
Model and use symbolic representations to
show changes within a system.
•
Explain how alpha and beta emissions create
changes in the nucleus of an atom that result in
the formation of new elements and energy
transformations.
•
Collect, analyze, and use data to predict the
identity of the nuclear products.
•
Model and make predictions based on data.
•
Create and use simulations.
•
How is half-life used to determine the
approximate age of a material?
•
How is fission different from fusion in terms of
energy and products produced?
•
Explain the concept of half-life.
•
Use the half-life principal to predict the
approximate age of a material.
•
Differentiate between fission and fusion in
nuclear reactions.
•
Differentiate between the relation of fission
and fusion to element changes and energy
formation.
Essential questions
•
•
What is the difference between alpha and beta
emissions in terms of the energy and size of the
particles and how does this determine the
product of a nuclear reaction?
How are new elements created in a nuclear
reaction?
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin
C-9
Chemistry, Quarter 1, Unit 1.3
2010-2011
Nuclear Changes (7 days)
Final, July 2011
Written Curriculum
Grade Span Expectations
PS 2 - Energy is necessary for change to occur in matter. Energy can be stored, transferred, and
transformed, but cannot be destroyed.
PS2 (9-11) INQ+SAE -6
Using information provided about chemical changes, draw conclusions about and explain the energy flow in a
given chemical reaction (e.g., exothermic reactions, endothermic reactions).
PS2 (9-11) –6 Students demonstrate an understanding of physical, chemical, and nuclear
changes by …
6c explaining and/or modeling how the nuclear make-up of atoms governs alpha and beta
emissions creating changes in the nucleus of an atom results in the formation of new elements.
6d explaining the concept of half-life and using the half-life principal to predict the approximate age of a
material
6e differentiating between fission and fusion in nuclear reactions and their relation to element
changes and energy formation.
Clarifying the Standards
Prior Learning
Students in grades K–4 learned how light rays behave. In grades 5–6, students learned about the transfer
heat energy. In grades 7–8, students learned the difference among conduction, convection, and radiation
and how energy travels through different materials by each of these methods.
Current Learning
The concept of nuclear reactions is introduced for the first time at the high-school level. Students learn the
structure of the nucleus and the nature of radioactive decay in terms of the particles emitted and the
resulting changes in the nucleus. The concept of half-life and how it is used to determine the relative age
of a substance is introduced. Students also learn to differentiate between fission and fusion in terms of the
necessary conditions and products of the reactions; that all nuclear reactions involve changes in energy;
and that nuclear radiation is a part of electromagnetic radiation. Through an investigation, students will
demonstrate the concept of half-life.
Future Learning
Students will use the concept of half-life to determine the age of rock structures. They will demonstrate an
understanding of the origin and evolution of galaxies and will explain the formation of the universe in
terms of the Big Bang theory. Students will demonstrate an understanding of processes and change over
time within the system of the universe and demonstrate an understanding of the life cycle of stars. In
biology courses the concept of radioactive tracers is used as a tool to determine biochemical pathways,
the age of fossils and artifacts.
C-10
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin
Nuclear Changes (7 days)
Final, July 2011
Chemistry, Quarter 1, Unit 1.3
2010-2011
Additional Research Findings
According to Benchmarks for Science Literacy:
Understanding the general architecture of the atom and the roles played by the main constituents of
the atom in determining the properties of materials now becomes relevant. Having learned earlier that
all the atoms of an element are identical and are different from those of all other elements, students
now come up against the idea that, on the contrary, atoms of the same element can differ in important
ways.
Students may at first take isotopes to be something in addition to atoms or as only the unusual,
unstable nuclides. The most important features of isotopes are their nearly identical chemical
behavior and different nuclear stabilities.
The idea of half-life requires that students understand ratios and the multiplication of fractions, and be
somewhat comfortable with probability. Games with manipulatives or computer simulations should
help them in understanding the idea of how a constant proportional rate of decay is consistent with
declining measures that only gradually approach zero. The mathematics of inferring backwards from
measurements to age is not appropriate for most students (p. 79).
Notes About Resources and Materials
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin
C-11
Chemistry, Quarter 1, Unit 1.3
2010-2011
C-12
Nuclear Changes (7 days)
Final, July 2011
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin
Chemistry, Quarter 1, Unit 1.4
Nuclear Applications
Overview
Number of instructional days:
10
(1 day = 53 minutes)
Content to be learned
Processes to be used
•
Describe various dating methods used to
determine the age of different rock structures.
•
Model dating methods.
•
•
Compare and contrast.
Calculate the age of rocks from various regions
using radioactive half-life.
•
Analyze data.
•
Given its constituent elements, isotopes, and
rate of decay, provide evidence for geologic
relationships between/among regions.
•
Determine the relative age of rock structures by
analyzing rock samples/rock data.
•
How can geologic relationships among regions
be determined?
Essential questions
•
How are dating methods used to determine the
age of rock structures similar, and how are
these dating methods different?
•
How can constituent elements, isotopes, and
rate of decay be used to calculate the age of a
rock sample?
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin
C-13
Chemistry, Quarter 1, Unit 1.4
2010-2011
Nuclear Applications (10 days)
Final, July 2011
Written Curriculum
Grade Span Expectations
ESS1 - The earth and earth materials as we know them today have developed over long periods of
time, through continual change processes.
ESS1 (9-11) INQ+POC+ MAS—4
Relate how geologic time is determined using various dating methods (e.g. radioactive decay, rock sequences,
fossil records).
ESS1 (9-11)—4 Students demonstrate an understanding of processes and change over time
by …
4a describing various dating methods to determine the age of different rock structures.
4aa calculating the age of a rocks from various regions using radioactive half life (given its
constituent elements, isotopes and rate of decay) and using those values to provide evidence for
geologic relationships between/among the regions.
4bb analyzing samples of rock to determine the relative age of the rock structure.
Clarifying the Standards
Prior Learning
In grades K–4, students learned how physical erosion reshapes the land. In grades 7–8, students evaluated
slow and fast processes to determine how the earth has changed over time, and in grade 9, students
learned how heat effects the rock cycle and plate movement. Element cycling within the earth was also
explored. Students in K–4 learned how light rays behave, and in grades 5–6, students learned about the
transfer of heat energy. In grades 7–8, students learned the difference among conduction, convection, and
radiation and how energy travels through different materials by each of these methods.
Current Learning
This unit requires students to apply their understanding of some key chemistry concepts that they learned
previously. Instead of approaching this as an earth science unit in a chemistry class, it should be
approached as a real-world application of chemistry principles. Students learn to describe various dating
methods and use data to determine the relative and absolute age of rock samples and other materials,
including the use of radioactive half-life to calculate the age of rocks and the analysis of the chemical
composition of rocks to determine geologic relationships among different regions. Students should
understand that rocks with similar chemical composition also have similar origins.
Future Learning
Students will engage in activities that help them understand how scientific theories about the structure of
the universe have been advanced through the sophisticated use of technology.
C-14
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin
Nuclear Applications (10 days)
Final, July 2011
Chemistry, Quarter 1, Unit 1.4
2010-2011
Additional Research Findings
According to the Atlas of Science Literacy, prior to this unit, students must understand that thousands of
layers of sedimentary rock have confirmed the long history of the changing surface of the earth and that
the youngest layers are not necessarily found on top—due to folding, breaking, and uplift (p. 51).
Additionally, the Science Curriculum Topic Study states that crustal dynamics and geochemical processes
provide a focus for understanding the solid earth (p. 68).
Making Sense of Secondary Science states that students may not fully understand the relative age of
igneous, metamorphic, and sedimentary rocks due to misunderstanding of the method of rock formation.
A brief review of rock types would eliminate this confusion (p. 113).
Notes About Resources and Materials
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin
C-15
Chemistry, Quarter 1, Unit 1.4
2010-2011
C-16
Nuclear Applications (10 days)
Final, July 2011
Cranston Public Schools, in collaboration with the
Charles A. Dana Center at the University of Texas at Austin